"""
Sharp RGB Colourspace
=====================

Define the *Sharp RGB* colourspace:

-   :attr:`colour.models.RGB_COLOURSPACE_SHARP_RGB`

References
----------
-   :cite:`Susstrunk2000` : Susstrunk, S. E., Holm, J. M., & Finlayson, G. D.
    (2000). Chromatic adaptation performance of different RGB sensors. In R.
    Eschbach & G. G. Marcu (Eds.), Photonics West 2001 - Electronic Imaging
    (Vol. 4300, Issue January, pp. 172-183). doi:10.1117/12.410788
-   :cite:`Ward2002` : Ward, G., & Eydelberg-Vileshin, E. (2002). Picture
    Perfect RGB Rendering Using Spectral Prefiltering and Sharp Color
    Primaries. Eurographics Workshop on Rendering, 117-124.
    doi:10.2312/EGWR/EGWR02/117-124
-   :cite:`Ward2016` : Borer, T. (2017). Private Discussion with Mansencal, T.
    and Shaw, N.
"""

from __future__ import annotations

import numpy as np

from colour.colorimetry import CCS_ILLUMINANTS
from colour.hints import NDArrayFloat
from colour.models.rgb import (
    RGB_Colourspace,
    linear_function,
    normalised_primary_matrix,
)

__author__ = "Colour Developers"
__copyright__ = "Copyright 2013 Colour Developers"
__license__ = "BSD-3-Clause - https://opensource.org/licenses/BSD-3-Clause"
__maintainer__ = "Colour Developers"
__email__ = "colour-developers@colour-science.org"
__status__ = "Production"

__all__ = [
    "PRIMARIES_SHARP_RGB",
    "WHITEPOINT_NAME_SHARP_RGB",
    "CCS_WHITEPOINT_SHARP_RGB",
    "MATRIX_SHARP_RGB_TO_XYZ",
    "MATRIX_XYZ_TO_SHARP_RGB",
    "RGB_COLOURSPACE_SHARP_RGB",
]

PRIMARIES_SHARP_RGB: NDArrayFloat = np.array(
    [
        [0.6898, 0.3206],
        [0.0736, 0.9003],
        [0.1166, 0.0374],
    ]
)
"""
*Sharp RGB* colourspace primaries.

Notes
-----
The primaries were originally derived from the :math:`M_{Sharp}` matrix as
given in *Ward and Eydelberg-Vileshin (2002)*:

    M_Sharp = np.array(
        [[1.2694, -0.0988, -0.1706],
         [-0.8364, 1.8006, 0.0357],
         [0.0297, -0.0315, 1.0018]])

    P, W = (
        array([[ 0.68976058,  0.32060751],
               [ 0.07358274,  0.90029055],
               [ 0.1166078 ,  0.0373923 ]]),
        array([ 0.33332778,  0.33334544]))

Private discussion with Ward (2016) confirmed he used the following primaries
and whitepoint:

    [0.6898, 0.3206, 0.0736, 0.9003, 0.1166, 0.0374, 1 / 3, 1 / 3]
"""

WHITEPOINT_NAME_SHARP_RGB: str = "E"
"""*Sharp RGB* colourspace whitepoint name."""

CCS_WHITEPOINT_SHARP_RGB: NDArrayFloat = CCS_ILLUMINANTS[
    "CIE 1931 2 Degree Standard Observer"
][WHITEPOINT_NAME_SHARP_RGB]
"""*Sharp RGB* colourspace whitepoint chromaticity coordinates."""

MATRIX_SHARP_RGB_TO_XYZ: NDArrayFloat = normalised_primary_matrix(
    PRIMARIES_SHARP_RGB, CCS_WHITEPOINT_SHARP_RGB
)
"""*Sharp RGB* colourspace to *CIE XYZ* tristimulus values matrix."""

MATRIX_XYZ_TO_SHARP_RGB: NDArrayFloat = np.linalg.inv(MATRIX_SHARP_RGB_TO_XYZ)
"""*CIE XYZ* tristimulus values to *Sharp RGB* colourspace matrix."""

RGB_COLOURSPACE_SHARP_RGB: RGB_Colourspace = RGB_Colourspace(
    "Sharp RGB",
    PRIMARIES_SHARP_RGB,
    CCS_WHITEPOINT_SHARP_RGB,
    WHITEPOINT_NAME_SHARP_RGB,
    MATRIX_SHARP_RGB_TO_XYZ,
    MATRIX_XYZ_TO_SHARP_RGB,
    linear_function,
    linear_function,
)
RGB_COLOURSPACE_SHARP_RGB.__doc__ = """
*Sharp RGB* colourspace.

References
----------
:cite:`Susstrunk2000`, :cite:`Ward2002`, :cite:`Ward2016`
"""
